A sliding-type portable terminal including a first housing and a second housing linearly movably coupled to the first housing face-to-face includes a spring module for opening/closing the first and second housings. The spring module includes at least a pair of asymmetrical S-shaped wires each including a first bend and a second bend extending from the first bend and having a greater curvature than the first bend. The spring module of the portable terminal provides a reduced thickness because of the spring action in the portable terminal, contributing in particular to an overall reduction in thickness of a sliding-type portable terminal and permit smooth opening/closing of the portable terminal.